下列命题正确的是（） A．若两个平面分别经过两条平行直线

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问题选择题

下列命题正确的是（　　）

A．若两个平面分别经过两条平行直线，则这两个平面平行

B．若平面α⊥γ，β⊥γ，则平面α⊥β

C．平行四边形的平面投影可能是正方形

D．若一条直线上的两个点到平面α的距离相等，则这条直线平行于平面α

答案

∵两个平面分别经过两条平行直线，两个平面可能相交，∴A不正确；

∵α⊥γ，β⊥γ，α与β可能相交，也可能平行，∴B不正确；

∵在正方体ABCD-A₁B₁C₁D₁中，取BB₁，DD₁的中点E、F，四边形AEC₁F为平行四边形，其在底面ABCD上的射影是正方形．∴C正确；

∵一条直线上的两个点到平面α的距离相等，两点在平面异侧时，直线与平面相交，∴D不正确；

故选C．

阅读理解

阅读理解。

The New Year is coming and as usual there are great hopes, dreams and resolutions to make.

However, I will stop hoping and dreaming this time and make the resolutions only.

First of all, I'm going to spend less time talking and more time doing. In the past (过去的) year, my

friends and I spent too much time talking nonsense (胡说八道). There is much work to do in the new

year, so I'm going to give the year to it.

Secondly, I'm going to spend less time in front of the TV and the computer. These are fun things but

they are also very time-wasting (浪费时间的). It's better to spend the time reading books.

Lastly, I'm going to join in fewer sports activities. It is better to do well in the lessons than on the

playground. The legs will get old and cannot play soccer for very long, but the mind will be much more

durable (持久的).

I made lots of resolutions but didn't keep them before. I'm not going to do that again in the new year.

I'll try my best to keep my resolutions.

根据短文内容，简答问题。

1. How many resolutions does the writer make for the new year?

______________________________________

2. What does the underlined word "it" refer to?

______________________________________

3. What is the writer going to do with the TV and the computer?

______________________________________

4. Why is the writer going to join in fewer sports activities?

______________________________________

5. What did the writer do with his resolutions before?

______________________________________

解答题